As described in historical dictionaries

Patronymica Britannica (1860)

FURNACE. Probably from Furness, CO. Lancaster, celebrated for its fine monastery ; perhaps, hovever, from residence near some great iron-furnace, before tlio existing method of smelting that metal was introduced.

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.


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